A cross-connect core for a telecommunications network of cross-connects may require a high density span termination system that transceives data. Such may be incorporated in a shelf consisting of a mechanical structure, back plane assembly, cabling, connectors and miscellaneous mechanical hardware. It may be designed to mount in a rack for containing a variable number of plug-in units which may be of different types. It may be designed so that no particular loading order is required so that in depopulated shelves, printed board assemblies may be plugged-in in any desired position.
One of the positions may be designed to accept a system alarm unit, for example, in the form of a plug-in printed board assembly. Such may be powered from a battery in a central office using a common return, for example. The shelf metal work may be connected to frame ground.
One or more of such termination systems may be connected to a cross-connect core for switching low speed signals such as DS-1 signals into and from a DS-1 interface of a high speed transport frame such as OC-1 for transmission to other cross-connects at other locations.
A basic requirement of such a termination system is to provide a low cost method of retrieving inventory (a record of plug-in unit types) electronically. Because there may be many such termination system units connected to a single cross-connect core, it may be burdensome for the network control therein to assume any inventory and alarm retrieval tasks on a regular basis. Moreover, at the beginning at least, not all of the unit positions in a given shelf will be used and an inventory and retrieval architecture must thus be designed to allow for growth while at the same time not overburdening system computational requirements at the early stage. And, it would be desirable to accomplish all of this at low cost. Thus there is a primary problem in designing an architecture that must provide basic electronic inventory and alarm retrieval at a low cost for an initial product while allowing the system to be upgraded with later plug-in unit options so the system supports electronic provisioning (electronically controlling a units transmission parameters and/or functionality).
Secondly, because of a potential for a large number, e.g., sixteen termination systems that may be connected to the cross-connect core, the architecture must minimize the amount of additional processing required by the telecommunication system network element which, without limitation, in the case illustrated, is a loop carrier cross-connect core having a dual network controller that carries out the network control function.
Lastly, the architecture should be of such a design, that it allows processors of various types and computational power to communicate over any interface therein.